The present application relates generally to computer models that test the dynamics of an automotive vehicle, and more particularly, to a method for operating a vehicle model in an aggressive or limit-seeking manner with understeer.
In the development of automotive vehicles, computer vehicle models are often used to test various designs. The various designs may be used to efficiently assess the handling of the vehicle using various parameters.
Current algorithms for computer driving control of computer vehicle models are designed to efficiently follow a given path. That is, the given path is accurately followed to provide minimal loss of speed due to side slipping of the computer vehicle model. Typically, such systems use a simulated look ahead of a driver to determine whether the vehicle is on the desired path. This is illustrated in step 10. In step 12 it is determined whether or not the vehicle is on target or on the desired path. If the computer vehicle model is on the desired path, step 14 is executed in which no change in the steering wheel angle is provided. The system then continues to step 16 in which the next time increment of the model is provided.
Referring back to step 12, if the vehicle is not on its intended path or on target step 18 is executed in which a new steering wheel angle (SWA) based on the size of the error between the look ahead path and the intended path is determined. In step 20 the computer model responds to the new steering wheel angle.
One problem with current computer vehicle models is that they are not typically designed to test the limits of control of the vehicle.
It would be desirable to be able to test the vehicle at aggressive or limit-seeking driving conditions. Typically, the computer model produces undesirable results that do not simulate real world driving when pushed to its limits. Typically, computer models generate undesirable steering wheel angles to compensate for variations in the desired path. The results are therefore not usable in the assessment of vehicle handling for such events. Therefore, it would be desirable to provide meaningful results when the vehicle model is driven aggressively, driven with understeer or oversteer.